revsets: support git refs

lib/src/revset.rs

@@ -34,12 +34,20 @@ pub enum RevsetError {
 // matching commits. Depending on how we decide to handle divergent git refs and
 // similar, we may also want those to resolve to multiple commits.
 pub fn resolve_symbol(repo: RepoRef, symbol: &str) -> Result<Commit, RevsetError> {
-    // TODO: Support git refs and change ids.
+    // TODO: Support change ids.
     if symbol == "@" {
         Ok(repo.store().get_commit(repo.view().checkout())?)
     } else if symbol == "root" {
         Ok(repo.store().root_commit())
     } else {
+        // Try to resolve as a git ref
+        let view = repo.view();
+        for git_ref_prefix in &["", "refs/", "refs/heads/", "refs/tags/", "refs/remotes/"] {
+            if let Some(commit_id) = view.git_refs().get(&(git_ref_prefix.to_string() + symbol)) {
+                return Ok(repo.store().get_commit(&commit_id)?);
+            }
+        }
+
         // Try to resolve as a commit id. First check if it's a full commit id.
         if let Ok(binary_commit_id) = hex::decode(symbol) {
             let commit_id = CommitId(binary_commit_id);

lib/tests/test_revset.rs

@@ -139,3 +139,86 @@ fn test_resolve_symbol_checkout(use_git: bool) {
 
     tx.discard();
 }
+
+#[test]
+fn test_resolve_symbol_git_refs() {
+    let settings = testutils::user_settings();
+    let (_temp_dir, repo) = testutils::init_repo(&settings, true);
+
+    let mut tx = repo.start_transaction("test");
+    let mut_repo = tx.mut_repo();
+
+    // Create some commits and refs to work with and so the repo is not empty
+    let commit1 = testutils::create_random_commit(&settings, &repo).write_to_repo(mut_repo);
+    let commit2 = testutils::create_random_commit(&settings, &repo).write_to_repo(mut_repo);
+    let commit3 = testutils::create_random_commit(&settings, &repo).write_to_repo(mut_repo);
+    let commit4 = testutils::create_random_commit(&settings, &repo).write_to_repo(mut_repo);
+    let commit5 = testutils::create_random_commit(&settings, &repo).write_to_repo(mut_repo);
+    mut_repo.insert_git_ref("refs/heads/branch1".to_string(), commit1.id().clone());
+    mut_repo.insert_git_ref("refs/heads/branch2".to_string(), commit2.id().clone());
+    mut_repo.insert_git_ref("refs/tags/tag1".to_string(), commit2.id().clone());
+    mut_repo.insert_git_ref(
+        "refs/tags/remotes/origin/branch1".to_string(),
+        commit3.id().clone(),
+    );
+
+    // Non-existent ref
+    assert_eq!(
+        resolve_symbol(mut_repo.as_repo_ref(), "non-existent"),
+        Err(RevsetError::NoSuchRevision("non-existent".to_string()))
+    );
+
+    // Full ref
+    mut_repo.insert_git_ref("refs/heads/branch".to_string(), commit4.id().clone());
+    assert_eq!(
+        resolve_symbol(mut_repo.as_repo_ref(), "refs/heads/branch").unwrap(),
+        commit4
+    );
+
+    // Qualified with only heads/
+    mut_repo.insert_git_ref("refs/heads/branch".to_string(), commit5.id().clone());
+    mut_repo.insert_git_ref("refs/tags/branch".to_string(), commit4.id().clone());
+    assert_eq!(
+        resolve_symbol(mut_repo.as_repo_ref(), "heads/branch").unwrap(),
+        commit5
+    );
+
+    // Unqualified branch name
+    mut_repo.insert_git_ref("refs/heads/branch".to_string(), commit3.id().clone());
+    mut_repo.insert_git_ref("refs/tags/branch".to_string(), commit4.id().clone());
+    assert_eq!(
+        resolve_symbol(mut_repo.as_repo_ref(), "branch").unwrap(),
+        commit3
+    );
+
+    // Unqualified tag name
+    mut_repo.insert_git_ref("refs/tags/tag".to_string(), commit4.id().clone());
+    assert_eq!(
+        resolve_symbol(mut_repo.as_repo_ref(), "tag").unwrap(),
+        commit4
+    );
+
+    // Unqualified remote-tracking branch name
+    mut_repo.insert_git_ref(
+        "refs/remotes/origin/remote-branch".to_string(),
+        commit2.id().clone(),
+    );
+    assert_eq!(
+        resolve_symbol(mut_repo.as_repo_ref(), "origin/remote-branch").unwrap(),
+        commit2
+    );
+
+    // Cannot shadow checkout ("@") or root symbols
+    mut_repo.insert_git_ref("@".to_string(), commit2.id().clone());
+    mut_repo.insert_git_ref("root".to_string(), commit3.id().clone());
+    assert_eq!(
+        resolve_symbol(mut_repo.as_repo_ref(), "@").unwrap().id(),
+        mut_repo.view().checkout()
+    );
+    assert_eq!(
+        resolve_symbol(mut_repo.as_repo_ref(), "root").unwrap(),
+        mut_repo.store().root_commit()
+    );
+
+    tx.discard();
+}